Clifford Chance and Gide had lead roles advising on a €3 billion ($3.4 billion) debt refinancing and credit-line extension tied to carbon-footprint reduction, a nascent but growing trend among companies and their bankers.

Eiffarie, a joint venture of the French infrastructure group Eiffage and the Australian financial group Macquarie, took out the debt to finance its 2006 acquisition of APRR, which runs the 2,300-kilometer autoroute network of superhighways through the eastern half of France.

The deal, which closed Feb. 27, refinanced €1 billion ($1.1 billion) of the original acquisition debt and renewed a €2 billion ($2.3 billion) credit line, Gide said in a statement. Both financings carry credit margins, or interest-rate premiums, linked in part to Eiffage's performance at improving health and safety and reducing its carbon footprint.